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URL of this page: //medlineplus.gov/ency/imagepages/19646.htm
Baker cyst
Overview
A Baker cyst is seen as a swelling behind the knee. It forms when joint fluid collects behind the knee. The swelling may be due from inflammation or from other causes, like arthritis. The condition can be seen in both adults and children.
Review Date 6/27/2026
Updated by: C. Benjamin Ma, MD, Chair, Department of Orthopaedic Surgery, Dr. Peter and Sophie Pappas Endowed Chair, V-nee Yeh Endowed Professor of Orthopaedic Surgery, University of California, San Francisco, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
